Japanese cryptocurrency exchange Bitbank has issued a formal warning to its customers regarding the use of prediction market platforms such as Polymarket, cautioning that accounts connected to such services could be suspended.
In a notice published on June 15, Bitbank said it remains committed to maintaining a safe trading environment in compliance with applicable laws and regulatory guidelines. As part of that effort, the exchange warned users about potential legal risks associated with prediction market services that allow participants to speculate on future events using cryptocurrencies.
Bitbank targets overseas event-betting platforms
Prediction market platforms have gained massive popularity over the last year, allowing users to trade on outcomes related to elections, sports events, political developments, and other future occurrences.
Bitbank specifically cited Polymarket as an example of a prediction market service, while also referring broadly to other platforms that offer betting-like functionality.
While many of these services are operated outside Japan, Bitbank warned that accessing them from within the country for financial gain could potentially be viewed as gambling or gambling-related activity under Japanese law.
“As a result, if we detect deposits or withdrawals related to prediction market services or services suspected of being related, we may suspend the customer’s account,” the exchange stated.
Severity of the account suspension
Bitbank outlined a range of restrictions that may be imposed if an account is suspended. Affected users could lose access to account logins, cryptocurrency deposits and withdrawals, Japanese yen withdrawals, and crypto asset trading services.
The company also noted that it would not be responsible for losses or damages resulting from account suspension measures taken under its compliance policies. For users who believe their accounts have been incorrectly flagged, Bitbank said they may contact the company through its official inquiry form to request a review.
The exchange also urged customers to exercise caution when interacting with third-party services and warned users against unknowingly becoming involved in activities that could create legal or compliance risks.
“As part of our efforts to prevent customers from becoming involved in crimes, disputes, or criminal activities, we ask customers to carefully consider the risks when using external services,” Bitbank said.
Growing global scrutiny
The warning comes as prediction markets continue attracting attention from regulators worldwide.
Platforms such as Polymarket have experienced significant growth by allowing users to speculate on political elections, economic data releases, sporting events, and geopolitical developments through blockchain-based markets.
However, regulators in multiple jurisdictions have questioned whether these services function more like financial prediction tools or unlicensed gambling platforms.
Japan has historically maintained strict regulations, and crypto exchanges operating under the country’s licensing framework face extensive compliance obligations related to anti-money laundering, consumer protection, and illegal financial activities.
Bitbank’s notice highlights the increasingly cautious approach taken by regulated crypto exchanges as authorities worldwide tighten oversight of digital asset activities.
Also read: Inside Polymarket’s Record $2.34 Billion FIFA World Cup 2026 Betting Frenzy
